This invention relates to fluid control apparatus, and more particularly to a ball valve and/or an actuator therefor.
In the past, a ball valve has been provided with an actuator and seal assembly exposed to the fluid flow. This seal has been susceptible to chattering and vibration because of the direct contact with the flow. The present invention is even more susceptible to such chattering and vibration because of a swivel mount to improve sealing.
Prior art exposed seal assemblies are susceptible to damage and to serious wear because of the chattering and vibration. This is true because the seal assembly seal receives large and rapid impact loads.
Prior art valves also scratch and damage seals on assembly or disassembly for repair or otherwise.
In the prior art in high pressure gas line it is also often the practice to use a power driven ball valve actuator and weld the ball valve in a pipeline with no access for repair or otherwise without cutting the valve out of the line with a torch and/or disassembling the actuator.
Prior art ball valves also consistently are provided with seals that fail to seal at low temperatures and/or have poor wear characteristics.